Slime controlling compositions and their use

ABSTRACT

The present invention relates to certain processes and compositions useful for inhibiting and/or controlling the growth of slime in water and, in particular, water employed for industrial purposes. Water employed in the manufacture of pulp paper and water employed in cooling water systems, as well as other industrial waters, provide environments which are conducive to slime formation. The novel composition of the present invention is a mixture which shows unexpected synergistic activity against microorganisms, including bacteria, fungi and algae, which produce slime in aqueous systems. The slime, of course, is objectionable from an operational and/or an aesthetic point of view. Specifically, the invention is directed to and the use of a composition comprising a combination of 3,5-dimethyl tetrahydro-1,3,5-2H-thiadiazine-2-thione or its derivatives and N-(2-nitrobutyl)morpholine or its derivatives. The compounds which are used in accordance with the present invention have been defined specifically. However, those compounds which are derivatives of the specific compounds and which possess the capacity to kill or inhibit the growth of slimeforming microorganisms such as bacteria, fungi and algae can also be substituted providing, of course, that the composition yields a synergistic composition for the purpose of controlling slime. The inventive composition inhibits the growth of slime in water, or more specifically, possesses biocidal activity against bacteria, fungi and/or algae.

United States Patent [191 Shema et al.

1*Jan. 14, 1974 SLIME CONTROLLING COMPOSITIONS AND THEIR USE [75]Inventors: Bernard F. Shema, Glenside; Robert H. Brink, Jr., Doylestown;Paul Swered, Philadelphia, all of Pa.

[73] Assignee: Belz Laboratories, Inc., Trevose, Pa.

[ Notice: The portion of the term of this patent subsequent to Mar. 7,I989, has been disclaimed.

[22] Filed: Oct. 14, 1971 [21] Appl. No.: 189,372

Related US. Application Data [63] Continuation-impart of Ser, No.00,443, Jan. 2,

1970, Pat. NO. 3,647,703.

[52] US. Cl 424/246, 71/67, 162/161, 424/248 [51] 1nt.Cl. A0ln 9/02,A0ln 9/22 [58] Field of Search 71/67 [56] References Cited UNITED STATESPATENTS 3,647,703 3/1972 Shemo et al. 21/58 Primary Examiner-James 0.Thomas, Jr. Attorney, Agent, or Firm- Alexander D. Ricci [57] ABSTRACTThe present invention relates to certain processes and compositionsuseful for inhibiting and/or controlling the growth of slime in waterand, in particular, water employed for industrial purposes. Wateremployed in the manufacture of pulp paper and water employed in coolingwater systems, as well as other industrial waters, provide environmentswhich are conducive to slime formation. The novel composition of thepresent invention is a mixture which shows unexpected synergisticactivity against microorganisms, including bacteria, fungi and algae,which produce slime in aqueous systems. The slime, of course, isobjectionable from an operational and/or an aesthetic point of view.Specifically, the invention is directed to and the use of a compositioncomprising a combination of 3,5 dimethyltetrahydro-l,3,5-2H-thiadiazine-Z-thione or its derivatives andN-(2-nitrobutyl)morpholine or its derivatives. The compounds which areused in accordance with the present invention have been definedspecifically. However, those compounds which are derivatives of thespecific compounds and which possess the capacity to kill or inhibit thegrowth of slimeforming microorganisms such as bacteria, fungi and algaecan also be substituted providing, of course, that the compositionyields a synergistic composition for the purpose of controlling slime.The inventive composition inhibits the growth of slime in water, or morespecifically, possesses biocidal activity against bacteria, fungi and/oralgae.

13 Claims, N0 Drawings SLIME CONTROLLING COMPOSITIONS AND THEIR USE Thisapplication is a continuation-in-part of application Ser. No. 443 filedJan. 2, 1970, now U.S. Pat. No. 3,647,703.

BACKGROUND OF THE INVENTION The formation of slime by microorganisms isa problem which attends many systems. For example, lagoons, lakes,ponds, pools and such systems as cooling water systems and pulp andpaper mill systems all possess conditions which are conducive to thegrowth and reproduction of slime-forming microorganisms. In bothone-through and recirculating cooling systems, for example, which employlarge quantities of water'as a cooling medium, the formation of slime bymicroorganisms is an extensive and constant problem.

Airborne organisms are readily entrained in the water from coolingtowers and find this warm medium an ideal environment for growth andmultiplication. Aerobic and heliotropic organisms flourish on the towerproper while other organisms colonize and grow in such areas as thetower sump and the piping and passages of the cooling system. Such slimeserves to deteriorate the tower structure in the case of wooden towers.In addition, the deposition of slime on metal surfaces promotescorrosion. Furthermore, slime carried through the cooling system plugsand fouls lines, valves, strainers, etc. and deposits on heat exchangesurfaces. In the latter case, the impedance of heat transfer can greatlyreduce the efficiency of the cooling system.

In pulp and paper mill systems, slime formed by microorganisms is alsofrequently and, in fact, commonly encountered. Fouling or plugging byslime also occurs in the case of pulp and paper mill systems. Of greatersignificance, the slime becomes entrained in the paper produced to causebreakouts on the paper machines with consequent work stoppages and theloss of production time or unsightly blemishes in the final product;this, of course, results in rejects and wasted output. The previouslydiscussed problems have resulted in the extensive utilization ofbiocides in cooling water and pulp and paper mill systems. Materialswhich have enjoyed wide spread use in such applications includechlorine, organo-mercurials, chlorinated phenols, organo-bromines, andvarious organosulfur compounds. All of these compounds are generallyuseful for this purpose but each is attended by a variety ofimpediments. For example, chlorination is limited both by its specifictoxicity for slime-forming organisms at economic levels and by theability of chlorine to react which results in the expenditure of thechlorine before its full biocidal function may be achieved. Otherbiocides are attended by high costs, odor problems and hazards inrespect to storage, use or handling which limit their utility. To date,no one compound or type of compound has achieved a clearly establishedpredominance in respect to the applications discussed. Likewise,1agoons, ponds, lakes and even pools, either used for pleasure purposesor used for industrial purposes for the disposal and storage ofindustrial wastes become, during the warm weather, besieged by slime dueto microorganism growth and reproduction. In the case of therecreational areas, the problem of infection, odor, etc. is obvious. Inthe case of industrial storage or disposal of industrial materials, themicroorganisms cause additional problems which must be eliminated priorto the materials use or the waste is treated for disposal.

It is the object of the present invention to provide a composition forcontrolling slime-forming microorganisms in aqueous systems, such ascooling water systems and pulp and paper mill systems, and forcontrolling slime formation or microorganism populations in aqueousbodies in general. Moreover, another object of the invention is theprovision of methods for preserving materials and for controllingslime-forming microorganisms in any aqueous system which is conducive tothe growth and reproduction of microorganisms and, in particular,cooling water and paper and pulp mill systems. These methods employ acombination of 3,5- dimethyl tetrahydro-l ,3,5-2H-thiadiazine-2-thioneand N-(2-nitrobutyl) morpholine and the respective derivatives of each.To be operable, the derivatives, of course, must possess the property ofbeing biocidally active against bacteria, fungi and/or algae, i.e.,either kill or inhibit the growth of these microorganisms.

In the practice of the invention, the combination is added to theparticular material to be preserved or to the system being treated, forexample cooling water systems, paper and pulp mill systems, pools,ponds, lagoons, lakes, etc., in a quantity adequate to control theslime-forming microorganisms which are contained by, or which may becomeentrained in, the system which is treated. It has been found that suchcompositions and methods control the growth and occurrence ofsuchmicroorganisms as may populate these particular systems.

GENERAL DESCRIPTION OF THE INVENTION As earlier stated, the inventivecomposition comprises a combination of 3,5-dimethyl tetrahydro-1,3,5-2H-thiadiazine-2-thione and a particular morpholine compound with eithercompound being present in such a quantity as to impart a synergisticbehavior for the purpose to the composition as a whole. Preferably, thecomposition contains a percentage by weight ranging from about 5 toabout percent of the morpholine compound. When these two ingredients aremixed either beforehand or by addition to the aqueous systemindividually, the resulting mixtures possess a high degree of slimicidalactivity which could not have been predicted beforehand from the knownactivity of the individual ingredients comprising the mixture.Accordingly, it is therefore possible to produce a more effectiveslime-control agent than has previously been available. Because of theenhanced activity of the mixture, the total quantity of biocide requiredfor an effective treatment may be reduced. In addition, the high degreeof biocidal effectiveness which is provided by each of the ingredientsmay be exploited without use of the higher concentrations of each. Thisfeature is not only important and advantageous from an economical pointof view, but also most desirable from the pollution or ecologicalstandpoints. In this regard, it might be pointed out that the smallerthe amount of a chemical that is required for effective treatment, thesmaller the problem in treating the wastes from these systems. In bothcooling water systems and in paper and pulp mill systems, certaindischarge of waste water, e.g., blowdown in cooling water systems, is anecessity. However, because of the current concern and legislationregarding the discharge of wastes, the effluent waste water must betreated to reduce and, hopefully, to eliminate any undesirableconstituents. This treatment, of course, is time-consuming and costly.Accordingly, a reduction in additive usage will result in acorresponding reduction in costs for the treatment of wastes containingthese additives.

To demonstrate the synergism which is obtainable from the combination ofthe morpholine compound with the 3,5-dimethyl tetrahydro-l,3,5-2H-thiadiazine- 2-thione (supplied by Stauffer Chemical Companyunder designation N-52l and the utility of the composition, thefollowing tests were conducted. As earlier indicated, synergisticactivity can be obtained by combining either the specific compounds oftheir derivatives providing, of course, the derivatives exhibit growthinhibitory or biocidal activity with respect to bacteria, fungi and/oralgae. The morpholine compound which was utilized for testing purposeswas N- (2-nitrobutyl) morpholine (supplied by R. T. Vanderbilt Companyunder designation Vancide F-5,609).

In order to illustrate the synergistic activity, the efficacy and thecomparative effectiveness of the inventive composition, various testswere utilized and will be described following.

The present invention differs from the invention of the parent case inthat the 2-thione compound has been where,

Q, =-Quantity of Compound A producing an end point (minimum inhibitoryconcentration) Q,, Quantity of Compound B producing an end point(minimum inhibitory concentration) Q4 Quantity of Compound A (in themixture) producing an end point Q Quantity of Compound B (in themixture) producing an end point For mixtures of Compounds A and B, andfor Compound A and Compound B acting alone, the following found toproduce synergistic activity with solely the N- 25 results wereobserved:

TABLE 1 Quantities Weight Ratio Producing End Points (ppm) A] 08/ OA/QB/ of A to B Q4 Q5 Mixture Qa Qb Qa Qb (Z-nitrobutyl) morpholine whichwas just one compo- It is evident from the data recorded in Table 1 thatn nt of the V derbilt co panys Vancide 1 -5386, the composition of thepresent invention functions to control slime growth due tomicroorganisms not only at SPECIFIC EMBODIMENTS equal portions of therespective ingredients, but also EXAMPLE 1 where just minor amounts ofone or the other are present. This discovery of synergism at the lowerlevels is SYNERGISTIC N 3 5 2H extremely valuable since it illustratesconclusively that l l f f Y1 tetrahydrol' the ingredients are compatibleover the wide percentth1adiaz1ne-2-thione ple.

SYNERGISTIC INDEX TEST Synergistic activity was demonstrated by addingCompound A and Compound B in varying ratios and over a range ofconcentrations to liquid nutrient medium which was subsequentlyinoculated with a standard volume of suspension of the bacteriumAerobacter aerogenes. Following two days incubation, the lowestconcentration of each ratio which prevented growth of age by weightrange.

BACTERICIDAL EFFECTIVENESS The bactericidal effectiveness of the mixtureof Compound A and Compound B of this Example is demonstrated by thefollowing Table in which the inhibiting power ofa 50/50 by weightmixture of A and B is shown. Aerobacter aerogenes was employed as thetest organism and a substrate technique was utilized. Specifically, thebiocidal mixture was added in gradually increasing quantities tonutrient agar media which was then inoculated with A. aerogenes. Thepreparation was then incubated for 48 hours. The values set forth in theTable indicate the quantity of biocide required, in parts by weight foreach one million parts by weight of the medium, in order to achievecomplete inhibition of the growth of the test organism.

TABLE 1A Quantity (ppm) required for inhibition Biocidal Material of A.aemgener Compound A (15%). Compound B (5%),

Inert 500 FUNGICIDAL EFFECTIVENESS In order to test the effectiveness ofthe inventive mixture in respect to fungi, evaluations were madefollowing the procedures described by B. F. Shcma and J. H. Conkey[Journal for the Technical Association of The Pulp and Paper Industry,36, 2OA-30A, (1953)]. The described procedure generally entailsincorporating the biocide under test in a nutrient substrate such asagar, malt, etc. and pouring the resulting medium into a Petri dish andallowing the medium to solidify. A button of fungus inoculum is placedon the surface of the solidified medium and the medium is incubated fora period of 14 days. After the period, the diameter of the colonycroorganisms but instead supply a practical demonstration of theefficacy of the biocide tested in relation to those communities ofmicroorganisms which have evidenced their ability to form slime inactual industrial systems.

In the testing of recirculating water samples, a substrate evaluationwas employed. In such testing, identical portions of water samples aretreated with varying concentrations of biocide and two portions are leftuntreated to serve as controls. The control portions are plated fortotal count at the beginning of biocide treatment and all portions areplated for total count at some suitable time period(s) after beginningbiocide treatment. Using the counts obtained from the plating, thepercentage kill (based on the initial control count) may be calculated.In the following example, the water sample was taken from a beater roomwhite water system at a mill in the northeastern United States.

For the purposes of comparison, the mixture of A and B was evaluatedtogether with a recognized Commercial Product.

TABLE 1C Quantity of Percent kill Biocidal Material biocide (ppm) after6 hours Compound A (15%), Compound B (5%), Inert (80%) 1.25 18 do. do.do. 2.5 42 do. do. do. 5.0 71 do. do. do. 12.5 88 do. do. do. 25.0 91do. do. do. 50.0 93

Commercial Product (22% active: Combination ofbis(trichloromethyhsulfone and methylene bisthiocyanate) 1.25 23 do. do.do. 2.5 do. do. do. 5.0 67 do. do. do. 12.5 85 do. do. do 25.0 91 do.do. 50.0

is measured and compared with the diameter of the button of inoculumoriginally placed upon the surface. If there is no increase in thediameter, the growth of the fungus is considered to be completelyinhibited and the treatment level which accomplished this is consideredthe inhibitory concentration. The fungal species uti lized as the testmicroorganisms to evaluate the efficacy of the present mixture werePenicillium expansum and Aspergillus niger.

A perusal of the recorded percentages clearly establishes that thecomposition of the present invention, al-

though less concentrated with respect to active ingredients as comparedto the Commercial Product, gave excellent rates of kill even at lowtreatment levels. As earlier expressed, excellent performance of abiocidal composition at low treatment levels not only provides a mostdesirable cost performance index, but also provides most desirableadvantages from the aspects of TABLE 18 Quantity (ppm) for inhibitionBiocidal Material P. expansum A. niger Compound A (15%), Compound B(5%), Inert (80%) SLIME CONTROL EFFECTIVENESS The inventive methods andcomposition were also tested with respect to their performance in thecontrol of slime formation in industrial systems. In this test anindustrial recirculating water was obtained from a system which wascurrently experiencing problems in respect to the formation of slime bymicroorganisms. Such tests do not demonstrate the efficiency of thebiocide employed with respect to specific species of mi- 20 percent byweight of the morpholine, from about I to 10 percent by weight of the3,5-dimethyl tetrahydrol,3,5-2H-thiadiazine-2-thione and the remaindercomposed of such materials as corrosion inhibitors, surfactants,stabilizers, organic solvents, such as alkanols, aromatic hydrocarbonsand/or water.

Surfactants such as the alkylaryl polyether alcohols, polyetheralcohols, sulfonates and sulfates, and the like, may be employed toenhance the dispersibility and stability of these dispersions. Theforegoing solutions of the biocidal compositions are utilized in orderto insure the rapid and uniform dispersibility of the biocides withinthe industrial water which is treated. It has been found that eitheraqueous or non-aqueous solvents are generally suitable in thepreparation of compositions of the invention, e.g., methyl cellosolve,organic solvents such as the aliphatic and aromatic hydrocarbons, e.g.,kerosene. Based upon the synergism study as outlined above, it wasascertained that in the treatment of paper mill and cooling water,effective biocidal action is obtained when the concentration ortreatment level of the combination or admixture of biocides is between0.1 parts per million to 1,000 parts per million, and preferably between1 and 100 parts per million, based upon the total content of the aqueoussystem treated, e.g., the total quantity of cooling water or paper millwater.

The compositions may also be utilized for the preservation of slurriesand emulsions containing carbohydrates, proteins, fats, oils, etc.;dosage levels for this purpose range from about 0.01 to about 5 percent.In accordance with this embodiment of the invention, the composition ismerely added and mixed with the material to be preserved.

The compositions of the invention which can be prepared by merelycombining the respective ingredients and mixingthoroughly at standardconditions may be fed continuously to the system to be treated, forexample by means ofa metered pump, or may be fed periodically atpredetermined intervals calculated to control the growth ofslime-forming organisms in the system. Naturally, in the treatment ofcooling water, the feeding of the inventive compositions must bedesigned to compensate for blowdown in those systems which employ thatexpedient.

Although the foregoing has been specifically directed to liquidformulations, the combinations of the invention may, of course, beformulated dry as powders or pelletized with well-known pelletizingagents, e.g., sodium chloride, talc, aluminate, etc. to produce solidpellets or briquettes which are added directly to the systems to betreated. The pellets or briquettes, of course, dissolve in accordancewith predetermined conditions or rates.

ln describing the inventive subject matter, the expression compositionhas been utilized. However, it is to be understood that physicalcompositions or combinations are not the sole utility of the invention.If, for example, the separate ingredients of the composition are addedindependently to a particular system, it is intended that this usage ofthe subject matter is within the scope of the invention and is to beconstrued within the broad interpretation of composition" and/orcombination."

As would be expected, the inventive composition may be added to thecooling water or paper and pulp mill systems at any convenient point.Naturally, in once-through or non-circulating systems, the compositionmust be added upstream from the point or points at which microorganismcontrol is desired. In circulating systems or pulp and paper systems,the compositions may be added at any point provided that the time lapseand the conditions experienced between point of addition and the pointat which the effect of the composition is to be experienced are not sodrastic as to result in the neutralization of the effect of thecomposition.

Although the invention has been described specifically as being directedto specific compositions comprising 3,5-dimethyltetrahydro-l,3,5-2H-thiadiazine- 2-thione in combination with themorpholine as de scribed in Example 1, it is obvious that homologs,analogs, etc. of the thiadiazine-2-thione compounds certainly areoperable for the purpose. Likewise, the derivatives of the speciallyexemplified morpholine compound also have utility in the presentinventive concept. Moreover, as earlier described, mixtures of thevarious derivatives would also serve the purpose. The provision, ofcourse, is that the derivatives possess biocidal or growth inhibitorycapacity with respect to bacteria, fungi and algae.

It should be noted that while the evidence has been derived from thetreatment of samples taken from paper and pulp mill aqueous systems, thecompositions and methods of the present invention are broadly applicableto the treatment of aesthetic waters as well as industrial waters suchas cooling waters which are plagued by deposits formed by slime-formingorganisms, or by the very presence of such organisms.

Having thus described the invention, what we claim 1. A method forcontrolling the growth of the microorganism Aerobacter aerogenes in anaqueous system in which said microorganism is found which comprisesadding to said system so as to contact said microorganism an effectiveamount of a combination comprising 3,5-dimethyltetrahydro-l,3,5-2H-thiadiazine-2-thione and N-(2-nitrobutyl)morpholine, wherein the weight ratio of the thione to the morpholine isfrom about 5 to percent to about 95 to 5 percent.

2. A method according to claim 1 wherein the combination containsapproximately 50percent by weight of each of said thiadia'zine-Z-thioneand said compound.

3. A method according to claim 1 wherein the combination is added tosaid system in any amount of from about 0.1 to about 1000 parts byweight of said composition per parts by weight of said aqueous system.

4. A method according to claim 3 wherein the composition is added tosaid system in an amount of 1 to parts per million parts of said aqueoussystem.

5. A method according to claim 3 wherein the aqueous system is theaqueous system of a cooling water system.

6. A method according to claim 3 wherein the system is the aqueoussystem of a pulp and paper mill system.

7. A method according to claim 1 wherein the aqueous system is theaqueous system of a cooling water system.

8. A method according to claim 1 wherein the system is the aqueoussystem of a pulp and paper mill system.

9. A method of preserving materials which are subject to attack by themicroorganism Aerobacter aerogenes which comprises incorporating in saidmaterial containing an amount of said microorganism from about 0.0] to 5percent by weight of a combination comprising 3,5-dimethyl tetrahydro-l,3 ,5-2l-lthiadiazine-Z-thione and N-(2-nitrobutyl) morpholine, whereinthe weight ratio of the thione to the morpho- 12. A biocidal productwhich is effective in controlling the growth of the microorganismAerobacter aerogenes in an aqueous system in which said microorganism isfound comprising from about 1 to 10 percent by weight of 3,5-dimethyltetrahydro-1,3,5-2H- thiadiazine-Z-thione and from about 5 to 20 percentby weight of N-(2-nitrobutyl) morpholine, and the remainder composed ofa material selected from the group consisting of surfactants,stabilizers, organic and inorganic solvents and mixtures thereof.

13. A product according to claim 12 wherein the product containsapproximately 5 percent of said thione and approximately 15 percent ofsaid morpholinc. l

2. A method according to claim 1 wherein the combination containsapproximately 50 percent by weight of each of said thiadiazine-2-thioneand said compound.
 3. A method according to claim 1 wherein thecombination is added to said system in any amount of from about 0.1 toabout 1000 parts by weight of said composition per parts by weight ofsaid aqueous system.
 4. A method according to claim 3 wherein thecomposition is added to said system in an amount of 1 to 100 parts permillion parts of said aqueous system.
 5. A method according to claim 3wherein the aqueous system is the aqueous system of a cooling watersystem.
 6. A method according to claim 3 wherein the system is theaqueous system of a pulp and paper mill system.
 7. A method according toclaim 1 wherein the aqueous system is the aqueous system of a coolingwater system.
 8. A method according to claim 1 wherein the system is theaqueous system of a pulp and paper mill system.
 9. A method ofpreserving materials which are subject to attack by the microorganismAerobacter aerogenes which comprises incorporating in said materialcontaining an amount of said microorganism from about 0.01 to 5 percentby weight of a combination comprising 3,5-dimethyltetrahydro-1,3,5-2H-thiadiazine-2-thione and N-(2-nitrobutyl)morpholine, wherein the weight ratio of the thione to the morpholine isfrom about 5 to 95 percent to about 95 to 5 percent.
 10. A compositionwhich is effective in controlling the growth of the microorganismAerobacter aerogenes in an aqueous system in which said microorganism isfound comprising 3,5-dimethyl tetrahydro-1,3,5-2H-thiadiazine-2-thioneand N-(2-nitrobutyl) morpholine, wherein the weight ratio of the thioneto the morpholine is from about 5 to 95 percent to about 95 to 5percent.
 11. A composition according to claim 10 wherein the compositioncontains approximately 50 percent by weight of each of saidthiadiazine-2-thione and said compound.
 12. A biocidal product which iseffective in controlling the growth of the microorganism Aerobacteraerogenes in an aqueous system in which said microorganism is foundcomprising from about 1 to 10 percent by weight of 3,5-dimethyltetrahydro-1,3,5-2H-thiadiazine-2-thione and froM about 5 to 20 percentby weight of N-(2-nitrobutyl) morpholine, and the remainder composed ofa material selected from the group consisting of surfactants,stabilizers, organic and inorganic solvents and mixtures thereof.
 13. Aproduct according to claim 12 wherein the product contains approximately5 percent of said thione and approximately 15 percent of saidmorpholine.